Sappan wood extraction for intelligent gelatin packaging films: a review on implementing green packaging solutions

Intelligent packaging (IP) is an enhanced version of traditional packaging systems, providing improved functionality. This technology enhances the communication of food packages with consumers by effectively indicating the shelf life, condition of food inside the package, and history of the product. This could increase the convenience of consumers and upgrade the product's safety. The IP system usually consists of an indicator system that gives an idea about the freshness of the product to the consumers. This color-changing indicator can be derived from natural sources such as fruits and vegetables, which contain pigments like anthocyanins, betalains, and curcumins. Sappan wood (Caesalpinia sappan L.) is a notable source of anthocyanin compounds, such as brazilin. The extract of Sappan wood, which could be extracted by various methods ranging from the traditional boiling method to the novel ultrasonic method, could be incorporated into a packaging film made from a biodegradable material like gelatin. The inclusion of this extract turns the normal gelatin film into a pH-dependent color-indicating film. The film changes color in response to pH shifts, which typically occur during food spoilage. Gelatin serves as a strong and compatible matrix for creating smart packaging films due to its solubility and compatibility with various natural extracts. By utilizing this underused resource, a smart packaging film can be developed, contributing valuable innovation to packaging technology.

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